Rolls for simultaneously reducing and relief-ribbing twist-drills.



S. DENK.

ROLLS FOR SIMULTANEOUSLY REDUCING AND RELIEF RIBBING TWIST DRILLS. APPLICATION FILED FEB. 24. 1913.

1,1 5 1 ,247 a Patented Aug. 24:, 1915.

[14 Iranian v -5 an oblique sectionjof thedrillfitting in the gieisi'r.

T all, tc/zpmJizLwiir scone-c1731.:

'i'lofiLsf Be it-know n that I; Srii'on, Dian a cit of the United States, residing in lirooklyn', in thelcounty of Kings StateptNew York, have lii361it8l certain new and useful I Improvements- 111, jrtolls to Sininltaneorisly generating,Twia-nri'n Reducing and,

of wh ich thegtollowing is a specification Ehis invention relates to; rollsifor twistin fluted rods 3 or olanks to form tWlSt-difilllS,

and for simultaneouslyTedircing the pr' eliin ir inarily-formed drill-blanks. and rolling relief-ribs on the blanks during the twisting operation,

p f cation, F gura sap a Vie hQWa ,ing a drill feeding between the .rolls, th

lower roll being shown in full lines and the upper roll in dottedilines .EigQZfls afront vicwof the lower-roll ,andof the drill being twisted and completed, as seen from below in Fi .1., .viewinline 11 Fig.

- sectional-view: in lineal-m igs 1 Similar characters designate like partsin all the figures.

Eigadis a fragmentary sectional, 1,... showing the lower part ofthe uppe z roll1,,andshow g channels ofthe roll-face. Fig. is a sim lar 1+0f apa t tion of the lower roll 2, with the drill in,

place thereon; Fig: 5 is a, front elevatiom.

- Figs. 31and 4L.

on a reduced scale, of the pairof rolls.

My present invention jsszin part in the, nature of an. improvement, on theidrill-twist ins rolls described inhLetters .Patent ofthe, United States No. V 7 61,880,..granted to me; June 7, 1904. In my; presentvimproyed rolls, howevenithe shapes and relative positons of the several component faces of thedrill-engaging surfaces are materially 'changed, as willbe evident by a; comparison ofthe drawings, especially of Figs. 3 and ..t .,of the presmt drawing with the corresponding views given in my said prior apatent. These changes involve a rotative change of position of the drill-blank relatively: to the roll-axes and a change of the roll-faces whereby to form the outer-surfaces of the drill-blank to a different shape, and the addition er new features consisting of roll-grooves located in a particular manner whereby to reshape the blank and form thereon the narrow projecting ribs along the forward edges of the lands, as hereinafter more fully set forth.

a I. stares rare Specification of Letters Patent.

orsion A cortronjiirionor YORK.

'soa'snifitrimadesnv nnnudine AND REIZIEF-RIBBING :twIsT-nnILLs.

" Patented Aii afi i, 1915.

551:; vii. Mu- };1'7 351,1 1 {5 5;}, g 1

Application filed February 24, 1913. Serial No. 750,085.

Tllhefdrill-blajnks may, in practice, be prelv ,nnar y formed by forging with suitable '1 I straight grooyes of flutes lengthwise of cyndricalrods and then twisted tojapproxiinate shape nsuch rolls as described in the aforesaid patent;t hese rolls being set at an angle to each other-and adapted for giving atwistto the gro.oves, so as to produce twist-drill .;QAslin that formerbase, the- 'present rollsare intended to work. upon axes wh ich are in parallel planes; butfthe axes are each located at 'an. ansle to the drill of about fifteen to twenty degrees and at an "angle to each other. or about thirty to forty de r sc I I The upper and lower rolls 1 and 2 are Qand respectively, these being preferably .h0rizontal- The upper axle "and roll may lie at an angle ofabout thirty degrees or gnore to the lower axle and roll, as will be understood from anexainination of Fig. 1. T he upp'er, rollhas a, circumferential ridge and the lower roll a ridge 6 for engaging within the opposite flutes 7 and 8 in the drill-blank these ridges being suitably roundedpr shaped. in section so as to match or nearlyinatch the grooves, and to hold the drill in the proper rotative position, as in over the lower ,roll 2 thatavertical line intersecting the axes of both rolls passes throughthe centers or crowns of both ridges 5 and 6, as will be understood byreference to Figs. 1, 2 andb. These ridges by reason ,7 oftheir crosswise arrangement become the principal factors in correctly twisting the drillrod 9. which is drawn horizontally between the rolls at an angle about as illus- ,.trated in Fig. 1 and in the drawing of said prior. patent. The movement ofthe drill vmay be effected bvthe grip of the rolls :thereon. these being power-driven and rotating in unison. 7

u Referring now to the lower roll 2, it will be seen that it is provided with a conical or flaring flange 10, which forms a shallow concave outward curve from the base 11 of one flank of the ridge 6, the purpose of this flange being to afford a support or guide for one side 12 of the drill-rod. Upon the opposite fiank of the ridge 6 is formed a flaring flange 13, which may also be slightly concaved and may be more abrupt than the mounted uponpower-driven arbors or axles i already referred to. p As in said prior patent, each of the flanges flange 10 and preferably does not extend I deeply into the roll, the inner termination of said flange or'its junction with the flank of the ridge being indicated at 14. In other words, the flank or side of the ridge 6 which joins the flange 13 is preferably not so deep 7 as the side which joins the ridge 10, as clearly seen in Figs. 2 and 4. The flange 13 is also intended to'assist in guiding the drill. The upper roll is similar to the lower roll, being provided with a flange 15, corre sponding to the lower flange 10, and also with a'flange 16,'corresponding to the lower flange 13; but it will be noted that the rolls are placed reversely, so that the flange 16 overlies the flange 10 and the flange 15 overlies the flange 13, thereby producing like effects upon diametrically opposite sides of the drill-rod as it feeds between the rolls. These features of the rolls operate in a gen- 7 eral way after the manner set forth in my aforesaid patent, but with the changes 10 and 13' cooperates independently with the ridge 6 in guiding or controlling the drill, and the sameis true of the flanges upon the upper roll, and while I prefer to use both flanges upon each roll, still my invention is not limited to rolls each having two flanges, so long as a flangeup on one roll' supports the drill upon a side diametrically opposite to the side of the rod which is supported by a like flange upon the other roll-that is, so

long as the rollshave reverse arrangement.

drill-supporting flanges 10, 13, 15, and 16 this difficulty is minimized or avoided;

Between the ridge 6 and the curved flange-face 10, of the lower roll 2, I make a rib-forming channel 11, having, prefer ably, an abrupt shoulder on its outer'side, as at 11*. Inrthe upper roll 1, a corresponding rib-forming channel is made at 31 between the ridge 5 and the flange surface15,

and said channel has a corresponding abrupt shoulder at 31*, Fig. 3. Beingthus formed,

Copiesof this patent may be obtained for when properly operated as set forth, the rolls are now adapted tosubstantially reduce the drill-blank by.a re-rolling of the same during and simultaneously with the final correction of the twist, andthus from an unribbed drill-blank to form the abruptly them to an accurate dimension, either-before or after hardening the drill; and this operationmay be repeated from time to-time as required, without thereby materially widening the bearing surface, which I in practice is an important advantage inthis' special class of drills, which are intended mainly for very coarse work,fas n shipyards and in bridge and boiler work,and

to be used without any finishing subsequent to the rolling, except on the relief ribs as here stated.

Having thus described my invention, I claim V 7 I 1. In a machine for forming fluted twistdrills, a pair of rolls mounted at an angle toeach other and each havinga circumferential ridge for forming drill-flutes, said ridge being flanked on each side with a concavo-cone-like drill supporting flange, one of said flanges beinglonger than the other and having its narrow end of less diameter than the narrow end of the other drill supporting flange, and a conc'avo-cone-like ribforming channel disposed at the narrow end of said longer flange adjacent to said ridge and thus remotely disposed from the enlarged endsv of said drill supporting flanges. r

2. In a'machine for forming fluted twistdrills, a pair of rollsmounted at anangle to eachother and each having a circumferential ridge for forming drill-flutes, said ridge being flanked on each side with a drill supporting flange, one of said flanges being longer than the other and having its narrow end of less diameter than the narrow end of the other'drill supporting flange, and a rib-forming channel disposed at the narnow end of said longer flange adjacent to said ridge and thus remotely disposed from the enlarged ends of said drill. supporting flanges.

Witnesses: I 7

JOHN J. .OBRLEN, MARY A. OCoNNoR.

Washington, I). 0. V

SIMON DENK' 

